International Journal of Science and Research (IJSR) ISSN (Online): 2319-7064 Index Copernicus Value (2013): 6.14 | Impact Factor (2013): 4.438 Volume 4 Issue 7, July 2015 www.ijsr.net Licensed Under Creative Commons Attribution CC BY Strabismus: - Symptoms, Pathophysiology, Management & Precautions Dr. Jayantilal Shah 1 , Dr. Shrikant Patel 2 1 Associate Professor, Department of Ophthalmology, Gujarat Adani Institute of Medical Science, Bhuj, Gujarat 2 Senior Lecturer, Department of Oral Pathology, Pacific Dental College & Hospital, Debari , Udaipur Abstract: Strabismus, more commonly known across-eyed or wall-eyed, is a vision condition in which a person cannot align both eyes simultaneously under normal conditions. One or both of the eyes may turn in, out, up or down. An eye turn may be constant (when the eye turns all of the time) or intermittent (turning only some of the time). Strabismus typically involves a lack of coordination between the extraocular muscles, which prevents directing the gaze of both eyes at once to the same point in space; it thus hampers proper binocular vision, and may affect depth perception adversely. Strabismus is primarily managed by ophthalmologists, optometrists, and orthoptists. Strabismus is present in about 4% of children. Treatment should be started as early as possible to ensure the development of the best possible visual acuity and stereopsis. Strabismus in children does not go away on its own and strabismus in adults is treatable, so strabismus treatment is necessary. Keywords: Strabismus, Etiology, Management. 1. Introduction Whereas many animals have eyes located on either side of their head (such as horses, for example), the eyes of humans look forwards – in the same direction. When normal, the eyes move in a coordinated manner, so that the object being looked at is centered in each eye. Because the eyes are set a small distance apart, the image in each eye is slightly different. The brain fuses the images coming from both eyes to produce a three-dimensional image that has depth. This three-dimensional vision, also known as stereoscopic or binocular vision, gives us depth perception. This allows us to judge distances more accurately, especially with objects close to us. Try to thread a needle with only one eye open and you will see the advantage of binocular vision! In order to achieve normal binocular vision, the eyes must see well, be aligned (looking in the same direction), and be focused properly on the same object. To maintain alignment, the eyes must also move in a coordinated manner, a process involving twelve different muscles (six in each eye). The four rectus muscles move the eyes up, down, to the right, and to the left, and the two oblique muscles have more complex actions, helping the eyes to look down and in (towards the tip of the nose) or up and in (towards the bridge of the nose).[1] Strabismus is a visual disorder where the eyes are misaligned and point in different directions. This misalignment may be constantly present, or it may come and go. Sometimes, only one eye is affected — turning inward (esotropia), outward (exotropia) or downward — while the other eye is directed straight ahead. Strabismus can also be described by its cause. The 3 cranial nerves (III, IV, VI) responsible for eye movement can be weak or paralyzed and cause strabismus. Some examples of paralytic strabismus include third nerve palsy and superior oblique palsy.[2] Strabismus prevents proper binocular vision and prevents both eyes from gazing the same point. Either peripheral vision or side vision may be affected. A patient‘s perception of depth is distorted. Perception of depth is the ability to recognize the order of objects in three dimensions. Patients will also experience a limited field of view. Some common terms for strabismus are "cross eyed," which means that one or both eyes turn toward your child‘s nose or "wall eyed," which means one or both eyes turn out toward your child‘s ears.[3] Etiology There are 6 muscles that work together to move your child‘s eye. Strabismus can happen when those muscles do not work together. This may be caused by a problem with the muscles, nerves, or a problem in your child‘s brain. Most people with strabismus are born with it and it tends to run in families. Strabismus may also be caused by:[4] Eye or head injuries Diseases that affect the nerves or muscles such as cerebral palsy or Down syndrome Brain tumors When your child‘s eyes do not work together to look at an object, your child‘s brain pays attention to the image from one eye and ignores the image from the other eye. This is called amblyopia or ―lazy eye.‖ If treatment does not take place early, the lazy eye may never see as well as the stronger eye. Sometimes the cause of strabismus is unknown. Other disorders associated with strabismus in children include: Apert syndrome, Cerebral palsy, Congenital rubella, Hemangioma near the eye during infancy, Incontinentia pigmenti syndrome, Noonan syndrome, Prader-Willi syndrome, Retinopathy of prematurity, Retinoblastoma, Traumatic brain injury, Trisomy 18. Strabismus that develops in adults can be caused by: Botulism, Diabetes (causes a condition known as acquired paralytic strabismus), Graves' disease, Guillain-Barré Paper ID: SUB156659 1510
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Strabismus: - Symptoms, Pathophysiology, Management ... · The primary sign of strabismus is a visible misalignment of the eyes, with one eye turning in, out, up, down or at an oblique
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International Journal of Science and Research (IJSR) ISSN (Online): 2319-7064
Index Copernicus Value (2013): 6.14 | Impact Factor (2013): 4.438
Volume 4 Issue 7, July 2015
www.ijsr.net Licensed Under Creative Commons Attribution CC BY
Strabismus: - Symptoms, Pathophysiology,
Management & Precautions
Dr. Jayantilal Shah1, Dr. Shrikant Patel
2
1Associate Professor, Department of Ophthalmology, Gujarat Adani Institute of Medical Science, Bhuj, Gujarat
2Senior Lecturer, Department of Oral Pathology, Pacific Dental College & Hospital, Debari , Udaipur
Abstract: Strabismus, more commonly known across-eyed or wall-eyed, is a vision condition in which a person cannot align both eyes
simultaneously under normal conditions. One or both of the eyes may turn in, out, up or down. An eye turn may be constant (when the
eye turns all of the time) or intermittent (turning only some of the time). Strabismus typically involves a lack of coordination between
the extraocular muscles, which prevents directing the gaze of both eyes at once to the same point in space; it thus hampers proper
binocular vision, and may affect depth perception adversely. Strabismus is primarily managed by ophthalmologists, optometrists, and
orthoptists. Strabismus is present in about 4% of children. Treatment should be started as early as possible to ensure the development of
the best possible visual acuity and stereopsis. Strabismus in children does not go away on its own and strabismus in adults is treatable,
so strabismus treatment is necessary.
Keywords: Strabismus, Etiology, Management.
1. Introduction
Whereas many animals have eyes located on either side of
their head (such as horses, for example), the eyes of humans
look forwards – in the same direction. When normal, the eyes
move in a coordinated manner, so that the object being
looked at is centered in each eye. Because the eyes are set a
small distance apart, the image in each eye is slightly
different. The brain fuses the images coming from both eyes
to produce a three-dimensional image that has depth.
This three-dimensional vision, also known as stereoscopic or
binocular vision, gives us depth perception. This allows us to
judge distances more accurately, especially with objects close
to us. Try to thread a needle with only one eye open and you
will see the advantage of binocular vision! In order to
achieve normal binocular vision, the eyes must see well, be
aligned (looking in the same direction), and be focused
properly on the same object. To maintain alignment, the eyes
must also move in a coordinated manner, a process involving
twelve different muscles (six in each eye). The four rectus
muscles move the eyes up, down, to the right, and to the left,
and the two oblique muscles have more complex actions,
helping the eyes to look down and in (towards the tip of the
nose) or up and in (towards the bridge of the nose).[1]
Strabismus is a visual disorder where the eyes are misaligned
and point in different directions. This misalignment may be
constantly present, or it may come and go. Sometimes, only
one eye is affected — turning inward (esotropia), outward
(exotropia) or downward — while the other eye is directed
straight ahead. Strabismus can also be described by its cause.
The 3 cranial nerves (III, IV, VI) responsible for eye
movement can be weak or paralyzed and cause strabismus.
Some examples of paralytic strabismus include third nerve
palsy and superior oblique palsy.[2]
Strabismus prevents proper binocular vision and prevents
both eyes from gazing the same point. Either peripheral
vision or side vision may be affected. A patient‘s perception
of depth is distorted. Perception of depth is the ability to
recognize the order of objects in three dimensions. Patients
will also experience a limited field of view. Some common
terms for strabismus are "cross eyed," which means that one
or both eyes turn toward your child‘s nose or "wall eyed,"
which means one or both eyes turn out toward your child‘s
ears.[3]
Etiology
There are 6 muscles that work together to move your child‘s
eye. Strabismus can happen when those muscles do not work
together. This may be caused by a problem with the muscles,
nerves, or a problem in your child‘s brain. Most people with
strabismus are born with it and it tends to run in families.
Strabismus may also be caused by:[4]
Eye or head injuries
Diseases that affect the nerves or muscles such as cerebral
palsy or Down syndrome
Brain tumors
When your child‘s eyes do not work together to look at an
object, your child‘s brain pays attention to the image from
one eye and ignores the image from the other eye. This is
called amblyopia or ―lazy eye.‖ If treatment does not take
place early, the lazy eye may never see as well as the stronger
eye. Sometimes the cause of strabismus is unknown.
Other disorders associated with strabismus in children